The present invention relates to lasers, and in particular, to a novel apparatus for combining the laser beams from a CW (continuous wave) laser with a TEA (Transverse Electrode Atmospheric) laser, and more particularly to such a laser device which has application in the medical and surgical fields.
The utility of the conventional continuous wave laser, for example, a CO.sub.2 laser, in surgery, has for years been enhanced by the ability of these lasers to produce a limited variety of pulsed waveforms, most often called "Super Pulse". These pulsed waveforms are really "gain switched" outputs that result from very brief (.about.100us to 600us) applications of pump power at levels somewhat above the normal limits of the laser operating in CW mode. The peak power and energy of these pulses in surgery can provide enhanced cutting effects for certain procedures. For example, the pulsing waveform minimizes the damage to adjacent tissue since the heat of the laser does not have time to conduct far from the site of impact during the brief moment of exposure. This is not true of a CW laser beam. The difference is a charring effect on the edge of a CW cut and a greater region of laterally affected tissue, caused by the continuous nature of the CW laser output.
The brief high bursts of energy have the effect of exploding away each tiny volume of tissue rather than slowly vaporizing, burning, or boiling the tissue away.
Unfortunately, there are limits to the magnitude of the energy and peak power that can be achieved when running a CW laser in the gain switched moded. With much greater peak power and energy, many new procedures are possible, i.e., bone cutting and the removal of cements that attach artificial joints to bones that need replacement, dental applications, and other instances where greater peak power is required.